thermal management of lcd displays supplier

Manufacturer of custom rugged displays for military, marine, industrial, avionic, medical, transportation, commercial and other applications. Diverse engineering team is able to design to fit any enclosure. Features include sunlight readable, NVIS, waterproof, flip-up, flip-down, rack mount drawer, panel or rack mount, and much more. All sizes are available from small to large. Suitable for workstations, cockpits, medical devices and other safety- or mission-critical applications. Manufactured, serviced, and supported in the USA.

As an LCD display used in outdoor advertising, it has much higher requirements for the use environment than a general display. During the use of outdoor LCD displays, due to different environments, they are often affected by severe weather such as high temperature, typhoons, rainstorms, and thunder and lightning. To keep the display safe and sound in severe weather, what preventive measures should we take?

First, anti-high temperature: Outdoor LCD displays usually have a large area, which consumes a lot of power during the application process, and the corresponding heat dissipation is also large. In addition, the external temperature is relatively high. If the heat dissipation problem cannot be solved in time, it is likely to be Causes problems such as short circuit heating of the circuit board. In production, ensure that the display circuit board is in good condition, and try to choose a hollow design in the housing design to help heat dissipation. During the installation, according to the device situation, insist that the display screen is in a good ventilation condition, and add heat dissipation equipment to the display screen when necessary, like installing an air conditioner or a fan inside to help the display screen dissipate heat.

Second, anti-typhoon: The outdoor LCD display has different installation positions and different installation methods, such as a wall-mounted, inlaid, pillar, and suspended. So in the typhoon season, in order to prevent the screen of the outdoor LCD display from falling, there are strict requirements on the load-bearing steel frame structure of the display. The engineering unit must design and install strictly in accordance with the standards of typhoon resistance, and at the same time have a certain degree of earthquake resistance to ensure that the outdoor LCD display will not fall and cause casualties and other hazards.

Third, anti-torrential rain: There is much rainy weather in the south, so the LCD display itself must have a high level of waterproof protection to avoid rain erosion. In the outdoor environment, the outdoor LCD display must reach the IP65 protection level, the module must be potted and packaged, the waterproof box is selected, and the module and the box are connected with a waterproof rubber ring.

1. Direct lightning protection: If the outdoor large LCD screen is not within the direct lightning protection range of nearby tall buildings, lightning rods must be installed LCD on the top or near the steel structure of the display;

2. Inductive lightning protection: The outdoor LCD display power system is equipped with 1-2 levels of power lightning protection, and the signal line is equipped with signal lightning protection. At the same time, the computer room power system is equipped with 3 levels of lightning protection, and the signal exit/entry equipment in the computer room is added. Install signal lightning protection device;

4. The front end of the outdoor LCD display and the grounding system of the computer room should meet the system requirements. Generally, the front-end grounding resistance should be less than or equal to 4 ohms, and the grounding resistance of the computer room should be less than or equal to 1 ohm.

The UT75A temperature controllers employ an easy-to-read, 14-segment large color LCD display, along with navigation keys, thus greatly increasing the monitoring and ...

The MultiCon CMC-99 is a powerful and versatile compact-multichannel-controller with a capability to record data, if the recording function is requested and activated. Thanks to that it is one of the first industrial ...

This is the latest generation of program and temperature controller, equipped with PID controller and Fuzzy logic control function. Ultra-bright LCD display ...

... channel and, in this complete version, it provides an RS485 Modbus RTU output for remote control.The unique 20-character LCD display allows easy programming parameters and alarm management and also to ...

PID temperature controller is a control loop feedback mechanism widely used in industrial control systems and a variety of other applications requiring continuously modulated control.

... control unit for flush mounting with LCD is used for temperature and humidity detection, setpoint adjustment and fan level adjustment. In combination with system and smartphone apps, a comfortable room ...

Liquid crystal displays (LCD) have become an essential component to the industry of display technology. Involved in a variety of contexts beyond the indoors like LCD TVs and home/office automation devices, the LCD has expanded its usage to many environments, such as cars and digital signage, and, thus, many temperature variations as well.

As with any substance that requires a specific molecular characteristic or behavior, LCDs have an operating temperature range in which the device, if within, can continue to function properly and well. In addition to that, there is also an ideal storage temperature range to preserve the device until used.

This operating temperature range affects the electronic portion within the device, seen as falling outside the range can cause LCD technology to overheat in hot temperatures or slow down in the cold. As for the liquid crystal layer, it can deteriorate if put in high heat, rendering it and the display itself defective.

In order for the LCD panel to avoid defects, a standard commercial LCD’s operation range and storage range should be kept in mind. Without adaptive features, a typical LCD TV has an operating range from its cold limit of 0°C (32°F) to its heat limit of 50°C (122°F) (other LCD devices’ ranges may vary a bit from these numbers).

The storage range is a bit wider, from -20°C (-4°F) to 60°C (140°F). Though these ranges are quite reasonable for many indoor and even outdoor areas, there are also quite a few regions where temperatures can drop below 0°C or rise above 32°C, and in these conditions, LCDs must be adapted to ensure functionality.

Heat, can greatly affect the electronics and liquid crystals under an LCD screen. In consideration of heat, both external heat and internally generated heat must be taken into consideration.

Seen as the liquid crystals are manipulated in a device by altering their orientations and alignments, heat can disrupt this by randomizing what is meant to be controlled. If this happens, the LCD electronics cannot command a certain formation of the liquid crystal layer under a pixel, and the LED backlighting will not pass through as expected, which can often lead to dark spots, if not an entirely dark image. This inevitably disrupts the display’s readability.

Depending on the upper limit of the operation temperature range, LCD device can be permanently damaged by extreme heat. With long exposure to extreme heat, besides the destruction of the liquid crystals, battery life can shorten, hardware can crack or even melt, response time may slow to prevent even more heat generation from the device.

The LED backlight and the internal circuitry, typically TFT-based in the common TFT LCDs, are components that can generate heat that damages the device and its display. To address this concern with overheating, many devices use cooling fans paired with vents.

But this leads to another problem: how can moisture be prevented from entering through the vent? If moisture enters the device and high heat is present, condensation can occur, fogging the display from inside, and in some cases, short-circuiting may cause the device to turn off. In order to circumvent this issue, the shapes of the air vents are specific in a way that allows only for air movement, not forms of moisture.

In the opposite direction is extreme cold. What typically occurs in the cold is “ghosting” (the burning of an image in the screen through discoloration) and the gradual slowing and lagging of response times. Like heat-affected LCD modules, the extreme temperature can affect the liquid crystals. This layer is a medium between the liquid and solid state, so it is still susceptible to freezing.

An LCD device can be left in freezing temperatures because it will likely not be permanently damaged like in the heat, but it is important to understand the device’s limits and how to take precautions when storing the device. The standard and most common lower-bound storage range limit is -20°C, below freezing, but if possible, it would be best to keep it above that limit, or else there is still a risk of permanent damage.

Display types have a lot of variation. Choices like alphanumeric or graphic LCD, human-machine interactive LCD modules and touchscreen panels capabilities, the width of the viewing angle, level of contrast ratios, types of backlighting, and liquid crystal alignment methods are often considered. For example, the twisted nematic LCD provides for the fastest response time at the lowest cost, but cannot offer the highest contrast ratio or widest viewing angle.

Environment-based factors must consider things besides the obvious temperature like UV exposure and humidity/moisture, as they all are necessary in finding the perfect fit extreme temperature LCD module.

Besides the LCD modules, recent new products have opened doors in wide temperature range displays, such as OLED displays. OLED displays offer better displays in regard to contrast, brightness, response times, viewing angles, and even power consumption in comparison to traditional LCD displays.

These benefits, in addition to its ability to achieve a wide temperature range, provide more options for consumers in search of high quality displays for extreme climates.

At low temperatures, the liquid crystal fluid maintains its viscosity, allowing the IC to refresh the data logic without any latency in the response time. At the high extreme of the operating temperature spectrum, the polarizer and adhesive materials are able to withstand the heat without warping the film and damaging the optical performance of the LCD module.

In addition to meeting the stringent quality requirements to withstand high temperature and humidity exposure, our displays also support “smart management” features, in form of a visual interface designed to help control the overall PV or EV application.

In cooler climates, the LCD fluid will slow down and change the response time of the display. We can install transparent heater films through an optical bonding process to maintain a sleek and modern display, as well as maintain display response time. The display heater will become active when the built in sensor detects a pre-set ambient temperature. This will protect the display from becoming overheated and conserve display power. We also work with you to ensure your display is in a proper enclosure that will retain the heat generated to prevent battery drainage. E3 enhancements to wide temperature displays can operate in the most rugged environments, maintain battery life, and exceed aesthetic standards.

Here is a picture inside the TV without the rear cover. The power supply includes the inverter stage for the backlight panel using only two HV transformers. Such design idea sounds very good because all EEFL tubes are connected in parallel avoiding the use of small transformers/inverters stages for each lamp minimizing in this way electronic issues on the backlight stage.

Compared to former CCLF, the new EEFL shows superior performance and applications. This incredible technology combines low power consumption and enhanced luminescence as compared to similar lighting sources. The most attractive feature of EEFL (External Electrode Fluorescent Lamp) is the absence of electrodes in the discharge tube, which is the main factor limiting lamp life. Electrode burn-out is the main cause of fault in CCFL. Because each CCFL lamp need its own ballast the new EEFL technology is simpler in electronics circuitry reducing in this way the rate of failures. EEFL lamps consist of a completely enclosed glass tube with external metal electrodes at both ends. This design minimizes electrode burn-out and results in a longer lamp life. Because the electrodes in former CCFL technology are in direct contact with the rare gasses, CCFL run warmer than the EEFL which are completely cool. On average, EEFL lamps have a lamp life of over 50,000 hours.

I figured out that three main areas on the circuit layout requires additional cooling. The hottest part was the digital class D audio amplifier (STA381BW) because overheats to much (manufacturer datasheet claims approx 3 watts of heat dissipation !!!) so I put a passive aluminum cooler to cool it down. Because the rear plastic cover touched the cooler I cut one of the corners. Using a smaller one was to weak to cool down the device at safe temperatures.

The digital scaler image MT5366 processor and glue logic ICs are located below a metallic RFI shield acting at the same time as a heatsink. Unfortunately the metal shield in use affects the efficiency on thermal conductivity of heat because is to thin leading to hot spots on the components. To correct such design issue the most convenient is to install a passive cooler. To cool down the MT5366 system on chip platform processor an older 486 mother board heatsink (the black one after changes third picture below) do the job well. The use of a thicker heatsink improves the thermal conductivity (spread of heat) avoiding hot spots on the devices.

The last part that requires additional cooling was the HDMI switch inputs selector (SiI9185 device schematic picture above) soldered on the right corner next to the HDMI inputs. Its based on the HDMI 1.3, DDC, HDCP specifications including a CEC (consumer electronics control) single wire bus interface to transmit I/O remote commands through a home network and EDID display identification (plug & play feature stored on serials EEPROMs). Researching datasheets from other versions I figured out that the device in operation consumes approximately 1.5 watts average but such information is not released by manufacturer. The device reach a working temperature of approximately 100 grads Celsius when HDMI inputs are enabled receiving stream data. Watching TV channels (digital DVB or analog cable) the HDMI switch remains cool because is in power down/suspend mode. At glance the HDMI switch overheats only when the inputs are enabled. Without an appropriate heatsink the life endurance of the device is affected because such operating condition can lead to a short circuit on terminals due silicon breakdown !!! . The HDMI switch integrates electrostatic discharge protections on its inputs up to 2kV discarding any possibilities of damages due weak ESD spikes but strong lightning electromagnetic discharges are a big problem without ESD protectors.

In the case of factory cooling all mentioned devices use the "ePad" enhancement, a small metal surface below the IC core case to transfer the silicon heat to PCB board. Despite the idea to reduce manufacturing costs avoiding in this way the use of external heatsinks such cheap PCB cooling solution is not appropriate at all. We verified on all the mentioned devices an excessive heat that unfortunately can lead to operational malfunctions/issues leading to a short durability.

After changes the overall heat is reduced due the improvements on heat conductivity and air convection cooling reducing the average working temperature on overall components avoiding at the same time hot spots on digital ICs (core of the silicon device).

To improve more the cooling on the T-Con LCD panel board we put a SinoGuide TCP400 series thermal pad on the main IC to increase the heat transfer on the metallic shield (this is more thick in diameter and seems to be OK for cooling purposes).

To resize a LCD is literally to cut the glass, polarizers, circuits and circuit boards to a new size. Years ago, it was thought impossible to preserve the original performance of a previously manufactured LCD once the glass circuits are cut. However, Litemax has done the impossible, over and over again, becoming the world"s leading pioneer and leader in LCD resizing solutions.

Squarepixel series is designed for high brightness with power efficiency LED backlight. It provides LCD panel with specific aspect ratios and sunlight readable for digital signage, public transportation, exhibition hall, department store, and the vending machines.

The spirit of Durapixel indeed lies with its name: durability. Why Durapixel? Commercial-grade LCD displays, due to the competitive pricing structure, are unable to offer more than MTBF of 30,000 hours, which will not be sufficient for any applications that require around-the-clock operations. System designers, integrators and users serious about rugged, industrial displays for demanding environments need to look no further – the unfailingly robust and high-quality Durapixel is the key to each of your success.

UbiPixel, industrial LCDs are used in many professional applications. High bright sunlight readable and low power consumption display technologies offer the highest quality LCDs for specific industrial applications. Our embedded LCD can be manufactured in an open frame, VESA mount, or fully enclosed housing for HMI display, KIOSK, Vending machine, home automation, point-of-sale terminals, digital signage and more. UbiPixel, industrial LCDs are used in many professional applications. High bright sunlight readable and low power consumption display technologies offer the highest quality LCD screen for specific industrial applications. Our embedded LCD can be manufactured in an open frame, VESA mount or fully enclosed housing for HMI display, KIOSK, Vending machine, home automation, point-of-sale terminals, digital signage and more.

Marine displays from Litemax are internationally recognized and certified with a proven track record of satisfying all types of scenarios, applications and environments for maritime professionals and organizations. Whether the project involves system building, maintenance, repair or equipment upgrade of a yacht, a submarine or any relevant maritime structure, Litemax"s marine displays guarantee high quality and performance from the dock to the engine room.

Litemax"s Mini-ITX embedded board provides the performance, expansibility, and durability to meet needs across a wide variety of applications, such as industrial control, industrial IOT, gaming, smart healthcare, and digital signage.

Featuring a modular designed, this series can be fitted with a number of modules to expand its base capabilities. On-site maintenance and future upgradability are easier than ever by deploying our panel PCs and monitors.

Litemax rugged panel PCs go beyond that of the standard industrial panel computes with elegant, full IP68/65-rated construction, powerful performance and flexible mounting options making it ideal for harsh environments and demanding applications, such as machine controller, command centers, and fast, efficient computing.

The Litemax ITRP series is fanless Passenger Information System, It features stretched LCD display, with high brightness to ensure easy readability even in light-insufficient environments. It serves as a reliable platform to provide passenger information on wide versatility of vehicles, such as bus and trams.

Litemax develops an embedded artificial intelligence application platform for AI edge computing to meet client vertical market applications and various needs and solve the changing challenges of the operating environment. In response to the increasing demand for AI computing, computer vision, deep learning, edge computing, etc., Litemax offers a series of fanless BOX PC with Intel Edge Computing and NVIDIA® Jetson Nano™ to effectively improve the cooling performance of fanless systems. Field applications can smoothly provide powerful computing performance, support high-level AI computing chips, and provide a solution platform for a variety of application scenarios to integrate software and hardware to create more flexible and better vertical functions. Simplify the manpower required for the client to invest in AI system integration.

Intel® offers the Intel® Smart Display Module (Intel® SDM) specification and reference design that can be integrated into the sleekest all-in-one designs. Intel® SDM delivers the same level of intelligence and interoperability as the Open Pluggable Specification, but in our smallest form factor yet eliminates the housing and advances the thinnest integrated displays.

The new Intel® Smart Kiosk Module (Intel® SKM) is a revolutionary solution that makes it easier to scale and maintain interactive kiosks, which are increasingly being used by businesses and governments worldwide to offer customers around-the-clock access to information and services.As the market for interactive kiosks increases, so does the demand for smarter multi-function kiosks with advanced capabilities such as workload consolidation, artificial intelligence, smartphone and social media integration, 5G connectivity, telepresence, remote manageability, and data analytics.

LITEMAX AD Board is with high speed Analog/ Digital conversion and minimal programming. A wide variety of computer interfaces are available in your choice.

Through intelligent thermal management technologies, Litemax is enabling smarter platforms for various vertical markets deploying display systems. Through the intelligent thermal control board, Litemax helps system integrators and engineers around the world improve efficiency and reliability.

BoldVu® displays deliver unparalleled visual performance in outdoor environments. With luminance ratings up to 5000 nits, their high-efficiency LED backlight and obsessively engineered optical stack achieve incredibly bright imagery in the face of intense sunlight – and will do so day-in and day-out for 10 full years. So bring on the sun, BoldVu’s got it managed.

Nothing will destroy a display faster than inadequate thermal management. CoolVu® is BoldVu’s multi-patented thermal management technology that extracts and expels heat from inside the BoldVu®, without exposing display electronics to ambient air or environmental contaminants, like dust, dirt and moisture and without the use of air filters – which means typically no periodic maintenance required. With CoolVu®, BoldVu® displays can operate in environments up to 122°F (50°C) without any degradation in visual performance.

BoldVu® displays are designed to live in a world of turbulence. ToughVu® cover glass shields delicate electronic components from the effects of adverse weather and vandalism. And with its low diffuse reflection, low haze, and anisotropy and bi-refringence qualities, ToughVu® glass ensures that digital imagery shines with brilliance and delivers maximum contrast, color accuracy, color saturation, and viewing angles.

As an added layer of intelligence, BoldVu® displays are equipped with a MEMS sensor which detects and reports on shock and impact events, so in the event of attempted vandalism, you’ll be in the know.

The world is full of spectacular color, and BoldVu® ensures that every one of them is accurately reproduced. The meticulously engineered optical stack achieves ultra-bright whites and super deep blacks so that every color in-between appears as vibrant as you could hope for. A billion colors never looked so good.

At the heart of BoldVu® is a sophisticated logic controller that receives data from electronic components within the display and autonomously optimizes parameters affecting image quality, chassis thermals, and power draw. With built-in intelligence, BoldVu® takes care of itself so you don’t have to.

With an embedded media player and a 13-megapixel camera capable of 4K video at 30fps, BoldVu® makes delivering amazing, interactive campaigns easier than ever. Output gorgeous graphics, measure audience engagement1 via the USB camera, and translate insights into more effective campaigns.

InfiniteTouch® is a next-gen PCAP touch sensor exclusively available on BoldVu® displays. Comprised of multiple layers of glass with index-matched sputter ITO conductors, containing no plastic films, InfiniteTouch® delivers high transmission, low reflection, and true tablet-like responsiveness, making it an incredible platform for delivering engaging interactive experiences.

The Internet of Things (IoT) is changing the way we live, work, and how cities and venues are able to offer digital services to the citizens and visitors they serve. As the IoT continues to grow the need for communications and data processing infrastructure grows with them.

An optional structure affixed atop BoldVu®, the Comms Cap is an additional housing for IoT and connectivity devices designed to extend functionality beyond the edges of the digital screen.

When you place a display out in the world, you never know what to expect. BoldVu® displays self-monitor and report on over 150 operating parameters and settings to the SmartVu® Portal. Via the secure web interface you can see how displays are performing, adjust what they’re doing, and troubleshoot errant behavior, all from anywhere you can access the internet.

BoldVu® LT Semi-Outdoor displays are designed for placement in areas protected from direct sun exposure, like in shopping malls and subway stations where its 850 nit operating luminance is bright but not overbearing.

BoldVu® outdoor displays are intended for deployment in areas out in the open and exposed to the elements. With a daytime operating luminance of 3500 nits BoldVu® is an excellent fit for a wide array of outdoor venues.

BoldVu® XT displays are for outdoor venues with big skies and ultra-bright sunlight like stadiums and raceways. When the sunglasses come out, the 5000 nit daytime luminance of BoldVu® XT still shines bright.

The CoolVu® thermal management system operates without air filters or coolants, requiring zero regular maintenance, while ensuring on-spec performance across temperature extremes (-40°C ~ +50°C / -40° F ~ +122° F).

With full product development, engineering, fabrication, assembly, and configuration under one roof, BoldVu® is a turnkey solution that makes deployment as easy as bolting to the ground, connecting power, and standing back in awe.

BoldVu® is built for as many components to be field replaceable as possible so in the event of part failure or vandalism, displays can be serviced in their installed position and back online with minimal downtime.

2 Intel, the Intel logo, and other Intel names and brands are the sole property of Intel Corporation or its subsidiaries in the US and/or other countries.

4 Power consumption based on full luminance with a white display field, averaged over 10 years of 24/7 use. All figures subject to change without notice.

BoldVu® displays deliver unparalleled visual performance in outdoor environments. With luminance ratings up to 5000 nits, their high-efficiency LED backlight and obsessively engineered optical stack achieve incredibly bright imagery in the face of intense sunlight – and will do so day-in and day-out for 10 full years. So bring on the sun, BoldVu’s got it managed.

Nothing will destroy a display faster than inadequate thermal management. CoolVu® is BoldVu’s multi-patented thermal management technology that extracts and expels heat from inside the BoldVu, without exposing display electronics to ambient air or environmental contaminants, like dust, dirt and moisture. With CoolVu®, BoldVu® displays can operate in environments up to 122°F (55°C) without any degradation in visual performance.

BoldVu® displays are designed to live in a world of turbulence. ToughVu® cover glass shields delicate electronic components from the effects of adverse weather and vandalism. And with its low diffuse reflection, low haze, and anisotropy and bi-refringence qualities, ToughVu® glass ensures that digital imagery shines with brilliance and delivers maximum contrast, color accuracy, color saturation, and viewing angles.

As an added layer of intelligence, BoldVu® displays are equipped with a MEMS sensor which detects and reports on shock and impact events, so in the event of attempted vandalism, you’ll be in the know.

The world is full of spectacular color, and BoldVu® ensures that every one of them is accurately reproduced. The meticulously engineered optical stack achieves ultra-bright whites and super deep blacks so that every color in-between appears as vibrant as you could hope for. A billion colors never looked so good.

At the heart of BoldVu® is a sophisticated logic controller that receives data from electronic components within the display and autonomously optimizes parameters affecting image quality, chassis thermals, and power draw. With built-in intelligence, BoldVu® takes care of itself so you don’t have to.

With an embedded media player and a 13-megapixel camera capable of 4K video at 30fps, BoldVu® makes delivering amazing, interactive campaigns easier than ever. Output gorgeous graphics, measure audience engagement1 via the USB camera, and translate insights into more effective campaigns.

InfiniteTouch® is a next-gen PCAP touch sensor exclusively available on BoldVu® displays. Comprised of multiple layers of glass with index-matched sputter ITO conductors, containing no plastic films, InfiniteTouch® delivers high transmission, low reflection, and true tablet-like responsiveness, making it an incredible platform for delivering engaging interactive experiences.

The Internet of Things (IoT) is changing the way we live, work, and how cities and venues are able to offer digital services to the citizens and visitors they serve. As the IoT continues to grow the need for communications and data processing infrastructure grows with them.

An optional structure affixed atop BoldVu®, the Comms Cap is an additional housing for IoT and connectivity devices designed to extend functionality beyond the edges of the digital screen.

When you place a display out in the world, you never know what to expect. BoldVu® displays self-monitor and report on over 150 operating parameters and settings to the SmartVu® Portal. Via the secure web interface you can see how displays are performing, adjust what they’re doing, and troubleshoot errant behavior, all from anywhere you can access the internet.

BoldVu® LT Semi-Outdoor displays are designed for placement in areas protected from direct sun exposure, like in shopping malls and subway stations where its 850 nit operating luminance is bright but not overbearing.

BoldVu® outdoor displays are intended for deployment in areas out in the open and exposed to the elements. With a daytime operating luminance of 3500 nits BoldVu® is an excellent fit for a wide array of outdoor venues.

BoldVu® XT displays are for outdoor venues with big skies and ultra-bright sunlight like stadiums and raceways. When the sunglasses come out, the 5000 nit daytime luminance of BoldVu® XT still shines bright.

The CoolVu® thermal management system operates without air filters or coolants, requiring zero regular maintenance, while ensuring on-spec performance across temperature extremes (-40°C ~ +50°C / -40° F ~ +122° F).

With full product development, engineering, fabrication, assembly, and configuration under one roof, BoldVu® is a turnkey solution that makes deployment as easy as bolting to the ground, connecting power, and standing back in awe.

BoldVu® is built for as many components to be field replaceable as possible so in the event of part failure or vandalism, displays can be serviced in their installed position and back online with minimal downtime.

2 Intel, the Intel logo, and other Intel names and brands are the sole property of Intel Corporation or its subsidiaries in the US and/or other countries.

4 Power consumption based on full luminance with a white display field, averaged over 10 years of 24/7 use. All figures subject to change without notice.

With its focus on industrial, instrumentation, hand-helds, medical and other low-to-medium volume markets makes Kyocera unique among liquid crystal display manufacturers. Kyocera’s TFT LCDs provide exceptional high-contrast ratio, color saturation, luminance and superior performance enhancements such as Advanced Wide Viewing (AWV) for true color fidelity, Super-High Brightness (SHB) and Wide Temperature range.

The use of liquid crystal displays (LCDs) in user interface assemblies is widespread across nearly all industries, locations, and operating environments. Over the last 20 years, the cost of LCD displays has significantly dropped, allowing for this technology to be incorporated into many of the everyday devices we rely on.

The odds are high you are reading this blog post on a laptop or tablet, and it’s likely the actual screen uses LCD technology to render the image onto a low-profile pane of glass. Reach into your pocket. Yes, that smartphone likely uses LCD technology for the screen. As you enter your car, does your dashboard come alive with a complex user interface? What about the menu at your favorite local drive-thru restaurant? These are some everyday examples of the widespread use of LCD technology.

But did you know that the U.S. military is using LCD displays to improve the ability of our warfighters to interact with their equipment? In hospitals around the world, lifesaving medical devices are monitored and controlled by an LCD touchscreen interface. Maritime GPS and navigation systems provide real-time location, heading, and speed information to captains while on the high seas. It’s clear that people’s lives depend on these devices operating in a range of environments.

As the use of LCDs continues to expand, and larger screen sizes become even less expensive, one inherent flaw of LCDs remains: LCD pixels behave poorly at low temperatures. For some applications, LCD displays will not operate whatsoever at low temperatures. This is important because for mil-aero applications, outdoor consumer products, automobiles, or anywhere the temperature is below freezing, the LCD crystal’s performance will begin to deteriorate. If the LCD display exhibits poor color viewing, sluggish resolution, or even worse, permanently damaged pixels, this will limit the ability to use LCD technologies in frigid environments. To address this, there are several design measures that can be explored to minimize the impact of low temperatures on LCDs.

Most LCD displays utilize pixels known as TFT (Thin-Film-Transistor) Color Liquid Crystals, which are the backbone to the billions of LCD screens in use today. Since the individual pixels utilize a fluid-like crystal material as the ambient temperature is reduced, this fluid will become more viscous compromising performance. For many LCD displays, temperatures below 0°C represent the point where performance degrades.

Have you tried to use your smartphone while skiing or ice fishing? What about those of you living in the northern latitudes - have you accidently left your phone in your car overnight where the temperatures drop well below freezing? You may have noticed a sluggish screen response, poor contrast with certain colors, or even worse permanent damage to your screen. While this is normal, it’s certainly a nuisance. As a design engineer, the goal is to select an LCD technology that offers the best performance at the desired temperature range. If your LCD display is required to operate at temperatures below freezing, review the manufacturer’s data sheets for both the operating and storage temperature ranges. Listed below are two different off-the-shelf LCD displays, each with different temperature ratings. It should be noted that there are limited options for off-the-shelf displays with resilience to extreme low temperatures.

For many military applications, in order to comply with the various mil standards a product must be rated for -30°C operational temperature and -51°C storage temperature. The question remains: how can you operate an LCD display at -30°C if the product is only rated for -20°C operating temperature? The answer is to use a heat source to raise the display temperature to an acceptable range. If there is an adjacent motor or another device that generates heat, this alone may be enough to warm the display. If not, a dedicated low-profile heater is an excellent option to consider.

Made of an etched layer of steel and enveloped in an electrically insulating material, a flat flexible polyimide heater is an excellent option where space and power are limited. These devices behave as resistive heaters and can operate off a wide range of voltages all the way up to 120V. These heaters can also function with both AC and DC power sources. Their heat output is typically characterized by watts per unit area and must be sized to the product specifications. These heaters can also be affixed with a pressure sensitive adhesive on the rear, allowing them to be “glued” to any surface. The flying leads off the heater can be further customized to support any type of custom interconnect. A full-service manufacturing partner like Epec can help develop a custom solution for any LCD application that requires a custom low-profile heater.

With no thermal mass to dissipate the heat, polyimide heaters can reach temperatures in excess of 100°C in less than a few minutes of operation. Incorporating a heater by itself is not enough to manage the low temperature effects on an LCD display. What if the heater is improperly sized and damages the LCD display? What happens if the heater remains on too long and damages other components in your system? Just like the thermostat in your home, it’s important to incorporate a real-temp temperature sensing feedback loop to control the on/off function of the heater.

The first step is to select temperature sensors that can be affixed to the display while being small enough to fit within a restricted envelope. Thermistors, thermocouples, or RTDs are all options to consider since they represent relatively low-cost and high-reliability ways to measure the display’s surface temperature. These types of sensors also provide an electrical output that can be calibrated for the desired temperature range.

The next step is to determine the number of temperature sensors and their approximate location on the display. It’s recommended that a minimum of two temperature sensors be used to control the heater. By using multiple sensors, this provides the circuit redundancy and allows for a weighted average of the temperature measurement to mitigate non-uniform heating. Depending on the temperature sensors location, and the thermal mass of the materials involved, the control loop can be optimized to properly control the on/off function of the heater.

Another important consideration when selecting a temperature sensor is how to mount the individual sensors onto the display. Most LCD displays are designed with a sheet metal backer that serves as an ideal surface to mount the temperature sensors. There are several types of thermally conductive epoxies that provide a robust and cost-effective way to affix the delicate items onto the display. Since there are several types of epoxies to choose from, it’s important to use a compound with the appropriate working life and cure time.

For example, if you are kitting 20 LCD displays and the working life of the thermal epoxy is 8 minutes, you may find yourself struggling to complete the project before the epoxy begins to harden.

Before building any type of prototype LCD heater assembly, it’s important to carefully study the heat transfer of the system. Heat will be generated by the flexible polyimide heater and then will transfer to the LCD display and other parts of the system. Although heat will radiate, convect, and be conducted away from the heater, the primary type of heat transfer will be through conduction. This is important because if your heater is touching a large heat sink (ex. aluminum chassis), this will impact the ability of the heater to warm your LCD display as heat will be drawn toward the heat sink.

Insulating materials, air gaps, or other means can be incorporated in the design to manage the way heat travels throughout your system on the way toward an eventual “steady state” condition. During development, prototypes can be built with numerous temperature sensors to map the heat transfer, allowing for the optimal placement of temperature sensors, an adequately sized heater, and a properly controlled feedback loop.

Before freezing the design (no pun intended) on any project that requires an LCD display to operate at low temperatures, it’s critical to perform low temperature first. This type of testing usually involves a thermal chamber, a way to operate the system, and a means to measure the temperature vs time. Most thermal chambers provide an access port or other means to snake wires into the chamber without compromising performance. This way, power can be supplied to the heater and display, while data can be captured from the temperature sensors.

The first objective of the low-temperature testing is to determine the actual effects of cold exposure on the LCD display itself. Does the LCD display function at cold? Are certain colors more impacted by the cold than others? How sluggish is the screen? Does the LCD display performance improve once the system is returned to ambient conditions? These are all significant and appropriate questions and nearly impossible to answer without actual testing.

As LCD displays continue to be a critical part of our society, their use will become even more widespread. Costs will continue to decrease with larger and larger screens being launched into production every year. This means there will be more applications that require their operation in extreme environments, including the low-temperature regions of the world. By incorporating design measures to mitigate the effects of cold on LCD displays, they can be used virtually anywhere. But this doesn’t come easy. Engineers must understand the design limitations and ways to address the overarching design challenges.

A full-service manufacturing partner like Epec offers a high-value solution to be able to design, develop, and manufacture systems that push the limits of off-the-shelf hardware like LCD displays. This fact helps lower the effective program cost and decreases the time to market for any high-risk development project.